Demand for microwave cookware, including cookware for popping grains such as popcorn, has grown with the rise in popularity of microwave ovens. This technology, while enthusiastically received, has presented myriad technical problems to those within the cookware industry concerned with providing the market with a satisfactory ovenware system for popping grain.
The industry has heretofore been unsuccessful in supplying an entirely satisfactory microwave ovenware system for popping grain because of the unique requirements placed upon such a system. For example, because a microwave oven is a convenience device, cookware therefore must be simple to use, easy to clean, and readily stored. Further, performance requirements dictate that such a system rapidly and completely cook the requisite amount of grain kernels with minimal waste. Moreover, since buttering capability is desirable, the assembly must provide means for melting and uniformly distributing a quantity of melted butter at the appropriate time upon the popped kernels. Finally, an acceptable system must be economically and readily manufacturable from microwave compatible materials.
Conventional electrical applicances for heating grains such as popcorn are well-known. Typically available devices provide a receptacle for receiving a quantity of grain, and exposing the kernels to a heat source, and a cover for containing the kernels during the popping cycle. The cover may be convertible into a container for serving the resultingly popped kernels for consumption as taught by U.S. Pat. No. 3,847,067.
However, this assembly is not appropriate for use in microwave ovens and is of a relatively complex and bulky configuration. Additionally, while in this known assembly there is provided a buttering device internally situated within the cover, the buttering device is not suited for microwave applications, and is not readily accessible during the cooking cycle.
Receptacles transparent to microwaves have been provided for popping grains. Such receptacles are preferably configured to provide a lower region of restricted internal volume for retaining the unpopped kernals in a massed grouping, and an upper region of greater volume for collecting and containing the popped grains. A preferred configuration for such a receptacle is conical, and is disclosed in general in U.S. Pat. Nos. 4,185,760 and 4,156,806. However, the receptacles of the type shown in the above patents require a specially designed supporting base or frame of microwave transparent material. Also, in such units a flat perforated lid is preferably provided for retaining popped kernels within the receptacle while allowing the escape of steam created by the heating of the kernels. Consequently, the capacity for storing popped grain is strictly limited by the downwardly restricted configuration of the conical wall. Moreover, receptacles of the representative type do not provide efficient externally accessible buttering means for melting and distributing molten butter on the popped kernels at an appropriate time.